John Deere 950 no start condition

[dockdave]

I have a John Deere 950 tractor. I went out the other day to use it , turned the key and got nothing. I pulled the starter out of the bell housing with the wiring still attached, turned the key and got nothing. The solenoid was kicking the gear in and out. I assumed it was my starter (it may be original). Put in the new starter and got nothing. My battery tests good, the engine turns by hand. I put a 2 amp charger on it, turned the key and got a buzzing noise from the voltage regulator, nothing else. I'm pretty sure I changed the regulator about 3 years ago. Does the regulator sound like the problem, or is there a way to test further before buying another regulator? Thanks in advance for any help.